Pi Day Celebrates a Mysterious Number In honor of 3.14, Dan Hellerich of PiDay.org joins other proud geeks in baking pies, writing "pi-kus" and other mathematical shenanigans.
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Pi Day Celebrates a Mysterious Number

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Pi Day Celebrates a Mysterious Number

Pi Day Celebrates a Mysterious Number

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Hey, check that out.

(Soundbite of music)

MARTIN: OK, we've said it a few times during the show. It's March 14, 2008, Pi Day if you didn't know. No, not the apple kind of pie, blueberry, it's a numerical pi. You know 3.14, March 14th, 3-14, get it? Pi is irrational and transcendental and sometimes even mysterious. Maybe you've seen the 1988 psychological thriller called "Pi" about a mathematical genius Max Cohen who sees patterns in everything.

(Soundbite of movie "Pi")

Mr. SEAN GULLETTE: (As Maximillian Cohen) If you graph the number of any system, patterns emerged. Therefore, there are patterns everywhere in nature. Maybe that pattern is like the pattern in the stock market.

Unidentified Actor: This is insanity, Max.

Mr. GULLETTE: (As Maximillian Cohen) Or maybe it's genius.

MARTIN: Indeed, maybe it's genius. While we looked into and there are apparently a lot of people who are pretty excited about the power of pi and today being Pi Day and all, we decided to get one such enthusiast on the line. His name is Dan Hellerich. He runs the website piday.org so he knows a lot of pi. Hey, Dan!

Mr. DAN HELLERICH (Pi Enthusiast): Hey, how are you?

MARTIN: How are you doing? Happy Pi Day.

Mr. HELLERICH: Yeah, Happy Pi Day to you, Rachel.

MARTIN: Hey thanks. Ah, Dan, what do you like about pi?

Mr. HELLERICH: As you said it's transcendental, it's the, digits after the decimal point go on forever and there is no pattern to pi, and so it's a kind of cool number and has a lot of, you know, real life application. Kids use it in geometry class, in junior high and earlier and it's just kind of in everything really.

MARTIN: So pi had been around along time clearly or forever, actually. But for people who don't know like me, who discovered Pi?

Mr. HELLERICH: Well, it was William Jones in the 1700s and then a mathematician named Euler later kind of decided to name it Pi, the Greek letter P because P is the first letter in periphery and perimeter and pi represents the perimeter of the circumference of a circle as it relates to how big the circle is - the diameter.

MARTIN: OK. Now, how much of pi do you know? In other words, how many of the numerals do you know by heart?

Mr. HELLERICH: Yeah, I don't know all that many. There are so many people on my website who know like ten times more than I do. I probably know like 15 or so digits after the decimal.

MARTIN: I think it is still pretty impressive, I got to tell you.

Mr. HELLERICH: Yeah, you really only need about 10 to be pretty precise when you are doing most math with geometry and physics and such.

MARTIN: Now why do you have a website? What's on your website? About Pi?

Mr. HELLERICH: Yeah. Well, I have a bunch of different things out here. I wanted to make a place where people could share their ideas about pi because they are, like I've said, I don't know all the digits so I want to find out who knows a lot of digits of pi. So there is a discussion section. I've had that for the last couple of years and people, you know, share their ideas for how to celebrate pi. A lot of teachers get on and share classroom plans and such. There are also lots of things - like you mentioned that movie "Pi" and...

MARTIN: I love that movie. Did you like that movie?

Mr. HELLERICH: I haven't seen it. I actually just bought it...


Mr. HELLERICH: And I'm going to watch it tonight.

MARTIN: But, there is this pi. Pi has kind of become part of pop culture in a way. It is this mysterious element unknown infinite thing.

Mr. HELLERICH: Right, yeah. So a lot of people are making YouTube videos. They're writing songs about pi and writing poetry related to pi, so we try and link them up and put some YouTube videos on the site.

MARTIN: Well, real quick. Today is Pi Day. Do you have specific celebration happening today, Dan?

Mr. HELLERICH: Yeah. Well, I'm going to pick up some pies on the way to my office, P-I-E, and rhubarb and apple pie and stuff like that and eat them at work and maybe after work, we'll hang out and...

MARTIN: Recite pi?

Mr. HELLERICH: Yeah, something like that.

(Soundbite of laughter)

MARTIN: Hey Dan Hellirich, he runs a website piday.org. Thanks for being with us on Pi Day, sharing some of Pi Day with us.

Mr. HELLERICH: Yeah, Happy Pi Day.

MARTIN: Hey thanks. Take care.

Mr. HELLERICH: You too. Bye.

MARTIN: OK so we are not done with Pi Day yet. It's just when you thought you'd already had enough pi. We're going to give you some more. Our producer Ian Chillag went to a Pi Day party, actually, a Pi Day pre-party. It happened one day early down at the NYU math club. So, how does the NYU math club get busy with some pi? Here's Ian's report.

Unidentified Man #1: So basically, here, all you do is you solve for X1 X2 and then you have your X3 is equal to R, X4 is equal to S.

Unidentified Man #2: OK.

CHILLAG: Isn't this supposed to be a party, guys? You guys are over here doing math on a chalkboard.

Unidentified Man #1: For me this is fun.

CHILLAG: Yes, there were people doing math equations on the chalkboard at a party and I did find one young woman doing homework. But it was a pretty fun shindig. I'll just let one party-goer set the scene for us. This is Jessica.

JESSICA: There are many pies on the table, and we're socializing and catching up and celebrating after very hard week of midterms.

CHILLAG: Now, Jessica was actually headed out the door. The room did clear out pretty early since a lot of the math club members had exams to work on. Spring break at NYU actually starts on Pi Day which was why they had the party on 3-13 instead of 3-14.

NITIN (Math Club President, New York University): All the math majors here are making a joke, saying that pi is minus 0.01 as you know, 3.13.

CHILLAG: That was Nitin (ph), the math club president. The 3.14 versus 3.13-thing was a point of contention around the room. But, then I ask these two guys, Kevin and Dan, what was so great about pi itself?

KEVIN: Well, you really can't find a square root of today. There is no date that I know of that will show up as square root of 2 is 1.69 or something.

Unidentified Man #4: Note if you had the square root of today, you'd have it on January 41st which obviously that does not work. You know, E is 2.718 so that would be February 71st that does not work either. You know, what other, you know, we have I but that is not a real number so how could we celebrate that?

CHILLAG: Anyway, then there was the main event, the Pi recitation contest. Nitin went first.

NITIN: 3.1415926537

Unidentified Woman: No.

(Soundbite of laughter)

CHILLAG: So there were couple of others and they have different styles of recitation. Some go really fast and was firing off numbers. Some do this kind of rhythmic thing. Then somebody asked Kevin if he wants in.

KEVIN: Sure why not. OK. Um, let's see. 3.1415926535897932384626433879...

Unidentified Woman: No.

(Soundbite of laughter)

CHILLAG: So, yeah, a lot of math at this party and then at the end, I saw this really kind of nerdy kid hunched over a piece of paper with this really cute girl and I was like, oh no, the nerd is doing the cute girl's homework. So I walked up to them to talk to them about it. He was writing down her number. I am not talking about 3.14.

(Soundbite of girls singing Pi)

Unidentified Girls: 3.141592653589793238462643384279502884197169399375125...

MARTIN: It's a lovely piece from BPP producer and director today Ian Chillag. He went to a Pi party. Thanks, Ian.

Unidentified Girls: 620899862089962080348253421170679821480865132863...

MARTIN: Don't go anywhere. Stay with us. Coming up next is NPR's Bob Boilen. He is live in Austin at the South by Southwest Festival. We'll see what bands are catching his eye and his ear. Plus, dreaming of Hilary or Barack or McCain. We'll check in with the Web site that logs people's dreams of the presidential candidates. Little bit scary, maybe. This is The Bryant Park Project from NPR News.

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